patch-2_6_7-vs1_9_1_12

[linux-2.6.git] / drivers / message / i2o / i2o_core.c

diff --git a/drivers/message/i2o/i2o_core.c b/drivers/message/i2o/i2o_core.c
index 36a745e..e5afe8d 100644 (file)
--- a/drivers/message/i2o/i2o_core.c
+++ b/drivers/message/i2o/i2o_core.c
@@ -213,6 +213,135 @@ static struct notifier_block i2o_reboot_notifier =
 
 static int verbose;
 
+#if BITS_PER_LONG == 64
+/**
+ *      i2o_context_list_add - append an ptr to the context list and return a
+ *                             matching context id.
+ *     @ptr: pointer to add to the context list
+ *     @c: controller to which the context list belong
+ *     returns context id, which could be used in the transaction context
+ *     field.
+ *
+ *     Because the context field in I2O is only 32-bit large, on 64-bit the
+ *     pointer is to large to fit in the context field. The i2o_context_list
+ *     functiones map pointers to context fields.
+ */
+u32 i2o_context_list_add(void *ptr, struct i2o_controller *c) {
+       u32 context = 1;
+       struct i2o_context_list_element **entry = &c->context_list;
+       struct i2o_context_list_element *element;
+       unsigned long flags;
+
+       spin_lock_irqsave(&c->context_list_lock, flags);
+       while(*entry && ((*entry)->flags & I2O_CONTEXT_LIST_USED)) {
+               if((*entry)->context >= context)
+                       context = (*entry)->context + 1;
+               entry = &((*entry)->next);
+       }
+
+       if(!*entry) {
+               if(unlikely(!context)) {
+                       spin_unlock_irqrestore(&c->context_list_lock, flags);
+                       printk(KERN_EMERG "i2o_core: context list overflow\n");
+                       return 0;
+               }
+
+               element = kmalloc(sizeof(struct i2o_context_list_element), GFP_KERNEL);
+               if(!element) {
+                       printk(KERN_EMERG "i2o_core: could not allocate memory for context list element\n");
+                       return 0;
+               }
+               element->context = context;
+               element->next = NULL;
+               *entry = element;
+       } else
+               element = *entry;
+
+       element->ptr = ptr;
+       element->flags = I2O_CONTEXT_LIST_USED;
+
+       spin_unlock_irqrestore(&c->context_list_lock, flags);
+       dprintk(KERN_DEBUG "i2o_core: add context to list %p -> %d\n", ptr, context);
+       return context;
+}
+
+/**
+ *      i2o_context_list_remove - remove a ptr from the context list and return
+ *                               the matching context id.
+ *     @ptr: pointer to be removed from the context list
+ *     @c: controller to which the context list belong
+ *     returns context id, which could be used in the transaction context
+ *     field.
+ */
+u32 i2o_context_list_remove(void *ptr, struct i2o_controller *c) {
+       struct i2o_context_list_element **entry = &c->context_list;
+       struct i2o_context_list_element *element;
+       u32 context;
+       unsigned long flags;
+
+       spin_lock_irqsave(&c->context_list_lock, flags);
+       while(*entry && ((*entry)->ptr != ptr))
+               entry = &((*entry)->next);
+
+       if(unlikely(!*entry)) {
+               spin_unlock_irqrestore(&c->context_list_lock, flags);
+               printk(KERN_WARNING "i2o_core: could not remove nonexistent ptr %p\n", ptr);
+               return 0;
+       }
+
+       element = *entry;
+
+       context = element->context;
+       element->ptr = NULL;
+       element->flags |= I2O_CONTEXT_LIST_DELETED;
+
+       spin_unlock_irqrestore(&c->context_list_lock, flags);
+       dprintk(KERN_DEBUG "i2o_core: markt as deleted in context list %p -> %d\n", ptr, context);
+       return context;
+}
+
+/**
+ *      i2o_context_list_get - get a ptr from the context list and remove it
+ *                             from the list.
+ *     @context: context id to which the pointer belong
+ *     @c: controller to which the context list belong
+ *     returns pointer to the matching context id
+ */
+void *i2o_context_list_get(u32 context, struct i2o_controller *c) {
+       struct i2o_context_list_element **entry = &c->context_list;
+       struct i2o_context_list_element *element;
+       void *ptr;
+       int count = 0;
+       unsigned long flags;
+
+       spin_lock_irqsave(&c->context_list_lock, flags);
+       while(*entry && ((*entry)->context != context)) {
+               entry = &((*entry)->next);
+               count ++;
+       }
+
+       if(unlikely(!*entry)) {
+               spin_unlock_irqrestore(&c->context_list_lock, flags);
+               printk(KERN_WARNING "i2o_core: context id %d not found\n", context);
+               return NULL;
+       }
+
+       element = *entry;
+       ptr = element->ptr;
+       if(count >= I2O_CONTEXT_LIST_MIN_LENGTH) {
+               *entry = (*entry)->next;
+               kfree(element);
+       } else {
+               element->ptr = NULL;
+               element->flags &= !I2O_CONTEXT_LIST_USED;
+       }
+
+       spin_unlock_irqrestore(&c->context_list_lock, flags);
+       dprintk(KERN_DEBUG "i2o_core: get ptr from context list %d -> %p\n", context, ptr);
+       return ptr;
+}
+#endif
+
 /*
  * I2O Core reply handler
  */
@@ -3551,6 +3680,10 @@ int __init i2o_pci_install(struct pci_dev *dev)
        c->short_req = 0;
        c->pdev = dev;
 
+#if BITS_PER_LONG == 64
+       c->context_list_lock = SPIN_LOCK_UNLOCKED;
+#endif
+
        c->irq_mask = mem+0x34;
        c->post_port = mem+0x40;
        c->reply_port = mem+0x44;
@@ -3788,3 +3921,6 @@ EXPORT_SYMBOL(i2o_event_ack);
 EXPORT_SYMBOL(i2o_report_status);
 EXPORT_SYMBOL(i2o_dump_message);
 EXPORT_SYMBOL(i2o_get_class_name);
+EXPORT_SYMBOL(i2o_context_list_add);
+EXPORT_SYMBOL(i2o_context_list_get);
+EXPORT_SYMBOL(i2o_context_list_remove);